This application is based on Japanese Patent Application No. 2000-30825 filed Feb. 8, 2000, the content of which is incorporated hereinto by reference.
1. Field of the Invention
The present invention relates to a card connector for electronic devices, such as cellular phones, telephones, PDAs (personal digital assistants), portable audio devices and digital cameras, and more specifically to a card connector which, although it occupies only a small space, can suitably accommodate at least two kinds of cards, one at a time, with different external shapes and different contact pad positions.
2. Description of the Related Art
In electronic devices such as cellular phones, telephones, PDAs and digital cameras, a variety of functions are added by inserting an IC card with a built-in CPU or memory IC, such as a SIM (subscriber identity module) card, an MMC (multimedia card) and an SD (secure digital; super density) card.
In a connector for removably accommodating such an IC card, a plurality of contact terminals made of a metal leaf spring are provided in a connector housing to contact a plurality of contact pads formed on the front or back surface of the inserted IC card to bring the IC card into electrical contact with the electronic device having that connector. The contact pads of the IC card include a power supply pad connected to a power supply line and a plurality of signal pads for transferring various signals. These contact pads are connected via the contact terminals of the card connector to a power supply circuit and various signal processing circuits in the electronic device.
Smart Media (trade name), one of such cards, is smaller in thickness and larger in surface size than other cards and therefore its contact pads are located at different positions than those of other cards. Comparison between the MMC card and the SD card shows that they differ in thickness although their surfaces are similar in shape and size and their contact pad positions are similar.
As described above, there are many IC cards of this kind with different external shapes and different contact pad positions. However, many conventional card connectors can only deal with one kind of card.
In the conventional art, if an electronic device is to accommodate two or more kinds of cards, it is necessary to prepare as many dedicated connectors as the number of different kinds of cards to be accommodated and mount them on a printed circuit board, giving rise to a problem of an increased connector-occupied area on the printed circuit board. On the electronic device side, as many card insertion openings as the number of different kinds of cards must be prepared, increasing the space the card connector occupies in the electronic device housing, which in turn prevents miniaturization of the electronic device.
In the industry of electronic devices using such IC cards, therefore, there has been a growing demand for a card connector structure that can removably accommodate in a single slot two or more kinds of cards with different external shapes and different contact pad positions.
The present invention has been accomplished under these circumstances and it is an object of this invention to provide a card connector occupying a small space and capable of removably accommodating in one and the same slot two or more different kinds of cards with different external shape and contact pad positions.
According to one aspect, the present invention provides a card connector for exchangeably accommodating at least two cards, or first and second cards, with different thicknesses, different sizes and different alignment positions of a plurality of contact pads, the card connector comprising; a first card accommodating portion defined by a pair of side walls for accommodating the first card, the side walls being adapted to guide side surfaces of the first card; a second card accommodating portion defined by a pair of side walls for accommodating the second card, the side walls being adapted to guide side surfaces of the second card; wherein the first card accommodating portion and the second card accommodating portion are formed in a connector housing so that a part of the first and second card accommodating portions can be used commonly by the first and second cards; and wherein a plurality of first contact terminals to be brought into contact with contact pads of the first card are arranged on one of an upper plate and a lower plate of the connector housing, and a plurality of second contact terminals to be brought into contact with contact pads of the second card are arranged on the other plate of the upper plate and the lower plate.
In this invention, the first card accommodating portion for accommodating the first card and the second card accommodating portion for accommodating the second card are formed in a connector housing so that a part of the first and second card accommodating portions can be used commonly by the first and second cards. This construction allows the first and second cards to be inserted into the connector through one and the same card slot.
First contact terminals to be brought into contact with a contact pads of the first card are arranged on one of an upper plate and a lower plate of the connector housing, and second contact terminals to be brought into contact with a contact pads of the second card are arranged on the other plate.
In this invention, therefore, the first card is inserted into the connector with its surface attached with the contact pads facing up or down so that the contact pads of the first card contact the first contact terminals arranged on one of the upper and lower plates. The second card is inserted into the connector with its surface attached with the contact pads facing up or down in a direction opposite that of the first card so that the contact pads of the second card contact the second contact terminals provided on the lower or upper plate opposite the first contact terminals.
According to another aspects the present invention provides a card connector for exchangeably accommodating at least two cards, or first and second cards, with different thicknesses, different sizes and different alignment positions of a plurality of contact pads, the card connector comprising: a first card accommodating portion defined by a pair of side walls for accommodating the first card, the side walls being adapted to guide side surfaces of the first card; a second card accommodating portion defined by a pair of side walls for accommodating the second card, the side walls being adapted to guide side surfaces of the second card; wherein the first card accommodating portion and the second card accommodating portion are formed in a connector housing so that a part of the first and second card accommodating portions can be used commonly by the first and second cards; and wherein a plurality of first contact terminals to be brought into contact with contact pads of the first card and a plurality of second contact terminals to be brought into contact with contact pads of the second card are arranged on one of an upper plate and a lower plate of the connector housing and at different positions.
In this invention, too, the first card accommodating portion and the second card accommodating portion are formed in the connector housing so that a part of these card accommodating portions can be used commonly by the first and second cards. This construction allows the first and second cards to be inserted into the connector from one and the same card slot.
In this invention, the first contact terminals and the second contact terminals are arranged on one of the upper and lower plates of the connector housing at staggered positions. This construction allows the first and second cards to be inserted into the connector with their faces directed in the same vertical direction.
Because the first card accommodating portion for accommodating the first card and the second card accommodating portion for accommodating the second card are formed in the connector housing so that a part of these card accommodating portions can be used commonly by the first and second cards, it is possible to insert into or remove from the same slot the cards with different external shapes and different contact positions. This in turn reduces the space occupied by the card connector, leading to a reduction in the size of various electronic devices.
The above and other objects, effects, features and advantages of the present invention will become more apparent from the following description of embodiments thereof taken in conjunction with the accompanying drawings.